The present invention relates to protocol testing of a communications network, and more particularly to a method and device for finding a reference pattern in a serial digital data stream.
For pattern recognition in a continuous binary data stream based on software, particularly for finding a reference pattern in a serial stream of digital data, there is a problem that microprocessors can only process data aligned bytewise (or multiples thereof). The data are usually provided bytewise by a hardware component, such as a memory, with the hardware component compiling the serial data stream in segments aligned bytewise. However, since the reference pattern to search for may appear at any position in the data stream, and thus does not necessarily have to be aligned bytewise, it is necessary, under the state of the art, to work with computationally time-consuming operations across several segments. In particular there are the repetitive operations of comparison, bitwise shifting, and “AND” and “OR” link use. When looking for longer reference patterns, the search proves time-consuming.
What is desired is to further develop a generic method so that finding a reference pattern in a serial data stream becomes possible in a shorter time span.